In engines with fuel injection, the injection of the fuel may take place either directly into the cylinders or into the intake tract, for example into the intake manifold or some other region of the intake tract situated upstream of the inlet valve of a cylinder. The first variant is realized in so-called direct injection systems, and the second variant is realized in so-called port fuel injection systems.
US 2010/0024771 A1 presents an injection system having a direct injection system and having a port fuel injection system and also having a valve for switching between the two injection systems. Two fuel pumps and two tanks are provided. The valve can switch different configurations of the components.
US 2010/0162619 A1 discloses an engine whose main water pump is activated and deactivated as a function of the temperature of the cooling liquid of the engine.
US 2010/0269791 A1 describes a direct injection system and a diagnostic system for a pressure sensor, in which, in a diagnostic mode, one of two fuel pumps connected in series is deactivated.
US 2009/0038587 A1 presents a method for controlling a direct injection system having a suction pump and having a pump for the fuel. A setting for cold starting ensures a fast pressure build-up, and a second setting with pump deactivation is provided for normal driving operation.
In engines equipped with both direct injection and port fuel injection, direct injection may be disabled but a pump may continue to operate. Dry operation of the piston may create excessive heat which may lead to leakage due to hot fuel deposit formation or wear on components.
The inventors herein recognize the above described disadvantages and disclose a systems and methods for an internal combustion engine having a direct injection system and having a port fuel injection system comprising: a pump for the direct injection system, wherein the pump can be activated and deactivated as a function of the activation of the direct injection system. The pump can thus be deactivated when the direct injection system is deactivated. In this way, overheating of a pump which is running dry may be prevented, which increases the service life and reliability of the pump and of the engine as a whole. In particular, it is possible to prevent a situation in which the pump or a piston is in motion even though no fuel is flowing through the pump.
The pump may, for activation and deactivation, be connected to a cam drive. It is possible in particular to use the technique which is used for the shutdown of cylinders. The pump may be mechanically connected to a drive system of the engine. Often, the drive of the pumps is derived from the drive system; this can also be realized with the present disclosure. Deactivation of the pump thus entails a mechanical decoupling of the pump from the drive system of the engine.
A system and methods are provided to deactivate a cam driven fuel pump. The system comprises a direct fuel injection system; a port fuel injection system; a pump for the direct injection system driven by a cam, wherein the pump can be activated and deactivated as a function of the activation of the direct injection system. Deactivating a pump when no fuel is pumped through it minimizes wear on pump components and increases efficiency.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. Further, the inventors herein have recognized the disadvantages noted herein, and do not admit them as known.